DE900228C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Membrane of great rigidity for sound reproduction
Assignee: Individual
•
Filing: 1937-01-20
•
Granted: 1953-12-21
•
Expires: 1957-01-20
Abstract
No abstract record available.
Inventors
- 👤 Dr Emil Podszus
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-11-09 12:30
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE551197C
Cited
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